23. Breathing
We breathe all the time
Although we do not pay much attention to it, we breathe all the time.
Breathing is an instinctual, automatic process.
The brain controls how heavily we breathe: if our body needs more oxygen, our breathing rate becomes more rapid.
Respiratory system
Breathing happens in two stages: inhalation and exhalation. In inhalation, air is breathed in to the lungs. In exhalation, air is released from the lungs.
When breathing, air travels into our bodies either through the nose or the mouth. From there, the air moves into the trachea, which is located in the throat. The trachea is divided into two bronchial tubes, which transport air to the lungs. The lungs are made of small, ball-shaped pulmonary alveoli.
When the air reaches a pulmonary alveolus, its oxygen is absorbed by the capillary vein of the alveolus. From there, the oxygen continues its journey to the heart and into the rest of the body.
At the same time as oxygen is absorbed into the capillary veins of the alveoli, harmful carbon dioxide is secreted from other capillary veins into the alveoli. The carbon dioxide is then released from the body during exhalation.
Protect your respiratory system!
The air around us is full of harmful substances. This is why breathing through your nose is healthier than breathing through your mouth. The hairs and mucuous membranes of your nose gather all the harmful substances before they can reach the lungs. Even the air that you breathe out during exhalation is not always clean. When sneezing or coughing, pathogenic viruses can spread into the environment.
Smoking is harmful to the respiratory system. Tobacco smoke contains many kinds of toxic substances that can damage your lungs.
Terminology
| Term | Explanation |
|---|---|
| respiration | A process in which we breathe air in and out of our body. |